Novel monofunctional substrates of polynucleotide phosphorylase. The "single-addition" of 2'(3')-O-dihydrocinnamoyl-nucleoside 5'-diphosphate to a primer oligonucleotide.

A method was developed for stepwise wynthesis of oligonucleotides of difined wequence using 2'(3')-O-dihydrocinnamoyl-nucleoside 5'-diphosphates as substrates for polynucleotide phosphorylase [ED 2.7.7.8]. Polynucleotide phosphorylase from Thermus thermophilus catalyzed the transfer of one 2'(3')-blocked ADP to the 3'-terminus of the primer trinucleoside diphosphate, ApApA. The product was 2'(3')-substituted triadenylyladenosine. The blocking group, dihydrocinnamoyl, could be removed completely from the product without destruction of the phosphodiester bond using alpha-chymotrypsin [ED 3.4.21.1] at neutral pH.